{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["Chemical"], "input": "Within this context , the Hedgehog ( Hh ) pathway has been implicated in several types of human tumors , and early clinical trials with Hh antagonists have validated Hh as a novel therapeutic target ."}
{"Chemical": []}